Maintain _id when copying index

Author: kremso

lib/es/utils.rb

@@ -10,7 +10,7 @@ def self.copy_index(from_index, to_index, opts = {})
 
     while results['hits']['hits'].any?
       requests = results['hits']['hits'].each_with_object([]) do |hit, requests|
-        requests << {index: {_type: hit['_type'], _id: hit['id']}}
+        requests << {index: {_type: hit['_type'], _id: hit['_id']}}
         requests << hit['_source']
       end
 
@@ -20,4 +20,4 @@ def self.copy_index(from_index, to_index, opts = {})
       results = from.scroll(scroll: scroll_timeout, scroll_id: scroll_id)
     end
   end
-end
+end